Electron diffusivities in MgB2 from point contact spectroscopy -: art. no. 224506

被引：16
作者：
Bugoslavsky, Y [1 ]
Miyoshi, Y
Perkins, GK
Caplin, AD
Cohen, LF
Pogrebnyakov, AV
Xi, XX
机构：
[1] Univ London Imperial Coll Sci Technol & Med, Blackett Lab, London SW7 2BZ, England
[2] Penn State Univ, Dept Phys, University Pk, PA 16802 USA
[3] Penn State Univ, Mat Res Inst, University Pk, PA 16802 USA
来源：
PHYSICAL REVIEW B | 2005年 / 72卷 / 22期
关键词：
D O I：
10.1103/PhysRevB.72.224506
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
We quantify the underlying physical mechanism behind the variation of the Andreev reflection with applied magnetic field in MgB2 epitaxial film and find good agreement with the theory for a dirty two-band superconductor. The important microscopic property, the ratio of electron diffusivities in the sigma and pi bands can be measured directly by means of Andreev reflection. We analyze results obtained for different directions of the applied field and determine the anisotropy of the diffusivities demonstrating that the anisotropic upper critical field is determined solely by the anisotropic diffusivity in the sigma band.
引用
收藏
页数：5
相关论文
共 27 条
  • [1] TRANSITION FROM METALLIC TO TUNNELING REGIMES IN SUPERCONDUCTING MICRO-CONSTRICTIONS - EXCESS CURRENT, CHARGE IMBALANCE, AND SUPER-CURRENT CONVERSION
    BLONDER, GE
    TINKHAM, M
    KLAPWIJK, TM
    [J]. PHYSICAL REVIEW B, 1982, 25 (07): : 4515 - 4532
  • [2] Multiband model for tunneling in MgB2 junctions -: art. no. 180517
    Brinkman, A
    Golubov, AA
    Rogalla, H
    Dolgov, OV
    Kortus, J
    Kong, Y
    Jepsen, O
    Andersen, OK
    [J]. PHYSICAL REVIEW B, 2002, 65 (18) : 1805171 - 1805174
  • [3] Superconducting gap structure and pinning in disordered MgB2 films
    Bugoslavsky, Y
    Miyoshi, Y
    Perkins, GK
    Caplin, AD
    Cohen, LF
    Zhai, HY
    Christen, HM
    Pogrebnyakov, AV
    Xi, XX
    Dolgov, OV
    [J]. SUPERCONDUCTOR SCIENCE & TECHNOLOGY, 2004, 17 (05) : S350 - S354
  • [4] Effect of magnetic field on the two superconducting gaps in MgB2 -: art. no. 132508
    Bugoslavsky, Y
    Miyoshi, Y
    Perkins, GK
    Caplin, AD
    Cohen, LF
    Pogrebnyakov, AV
    Xi, XX
    [J]. PHYSICAL REVIEW B, 2004, 69 (13) : 132508 - 1
  • [5] The origin of the anomalous superconducting properties of MgB2
    Choi, HJ
    Roundy, D
    Sun, H
    Cohen, ML
    Louie, SG
    [J]. NATURE, 2002, 418 (6899) : 758 - 760
  • [6] Erwin SC, 2003, PHYS REV B, V68, DOI 10.1103/PhysRevB.68.132505
  • [7] Vortex imaging in magnesium diboride with H⊥c -: art. no. 100508
    Eskildsen, MR
    Jenkins, N
    Levy, G
    Kugler, M
    Fischer, O
    Jun, J
    Kazakov, SM
    Karpinski, J
    [J]. PHYSICAL REVIEW B, 2003, 68 (10)
  • [8] Vortex imaging in the π band of magnesium diboride -: art. no. 187003
    Eskildsen, MR
    Kugler, M
    Tanaka, S
    Jun, J
    Kazakov, SM
    Karpinski, J
    Fischer, O
    [J]. PHYSICAL REVIEW LETTERS, 2002, 89 (18)
  • [9] GOLUBOV A, COMMUNICATION, P35416
  • [10] Upper critical field in dirty two-band superconductors: Breakdown of the anisotropic Ginzburg-Landau theory
    Golubov, AA
    Koshelev, AE
    [J]. PHYSICAL REVIEW B, 2003, 68 (10)
123